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    <title>Document</title>
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<body>
    <ul>
        <li>1111</li>
        <li>2222</li>
        <li>3333</li>
    </ul>
    <script src="./js/jquery-1.12.4.js"></script>
    <script>
        $(function(){
            // $("li:eq(0)") 整体是一个jquery对象
            $("li:eq(0)").html();

            $("li").each(function(index,element){
                // element 是一个原生js对象
                console.log($(element).html()); // each.html:19  Uncaught TypeError: element.html is not a function
                console.log(index);
                console.log(element.innerHTML);
                console.log("---------------------");
            });

            console.log("***********************");
            $("li").each(function(){
                // $(this) 是一个jquery对象
                console.log($(this).text());
            });

            console.log($("ul").height());
            console.log($("ul").width());




        })
    </script>
</body>
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